There are various application fields for systems in which quite a number of magnetic circuits are placed in a relationship of mutual influence, without any magnetizable parts being in direct contact. This is the case, e.g., when a number of solenoid valves are disposed closely spaced in an in-line array.
The smaller the solenoid valves in terms of their outer dimensions and the closer they are to be arranged next to each other for reasons of space, the greater the extent of undesirable mutual influence of the magnetic circuits on each other. This is accompanied by losses of energy. Magnetic flux does not stay within an apparatus, but flows off, ineffective in terms of power for this apparatus, via neighboring, magnetically conductive metal parts or is redirected to neighboring magnetic circuits. In the most unfavorable case, it may happen that a valve is unintentionally also switched when its neighboring valve switches.
Solenoid valves that are arranged side by side therefore require a higher voltage for switching or are no longer responsive at all.